Purewell 3-Stage PW-OB
A low-priced, certified-filter 2.25 gal system for chlorine, taste and sediment. Fluoride needs a different model.
Amazon $145.99$145.99
2.2 galNSF/ANSI 42, NSF/ANSI 3723,000 gal each
3.5/5
A well-priced 2.25 gal system with certified carbon filters. The easy pick if you want Berkey-size capacity for less.
- 2.2 galCapacity
- NSF/ANSI 42, NSF/ANSI 372Certification
- 3,000 gal eachElement life
- Add-on filterFluoride
Check price at Amazon$159.99
Price checked November 9, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Certified filter and system at a low price
- Room to add two fluoride filters later
Cons
- Does not reduce fluoride as shipped
- Only a one-year warranty
The Waterdrop King Tank family
Every Waterdrop King Tank model we rank, smallest first. Ratings compare each against its own capacity.
| Model | Capacity | Rating | Price |
|---|---|---|---|
| Waterdrop TK15-A | 1.5 gal | 3.4/5 | $119.99 |
| Waterdrop TK-A (this one) | 2.2 gal | 3.5/5 | $159.99 |
| Waterdrop TK-AE | 2.2 gal | 3.0/5 | $189.99 |
| Waterdrop TK-AB-FS | 2.2 gal | 3.3/5 | $199.99 |
| Waterdrop TK-FS | 2.2 gal | 3.3/5 | $239.99 |
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its capacity. How we rank explains each one.
Specifications
| Model number | WD-TK-A |
|---|---|
| Capacity and flow | |
| Tank capacity | 2.2 gal |
| Price per gallon of capacity | $71.11 |
| Elements included | 2 |
| Maximum elements | 2 |
| Filtration | |
| Element type | Coconut shell carbon filter (black) |
| Certified | NSF/ANSI 42, NSF/ANSI 372 |
| Certification detail | Listing: system passed NSF/ANSI 372 (lead-free materials) and the black carbon filter is certified to NSF/ANSI 42 for chlorine, taste and odor. |
| Fluoride | Add-on filter |
| Running cost | |
| Rated life per element | 3,000 gal each |
| Replacement element | 35 $ |
| Cost per gallon filtered | $0.012 |
| Build | |
| Material | 304 stainless steel |
| Warranty | 1 year |
Alternatives in this capacity
Culligan MaxClear Scout 1 Filter
The entry Culligan MaxClear with a certified filter for people who want a name-brand 2.25 gal system at a low price.
Amazon $155$155
2.2 galNSF/ANSI 42
Waterdrop TK15-A
A small, low-priced certified gravity filter for one to three people, a trip or an RV.
Amazon $119.99$119.99
1.5 galNSF/ANSI 42, NSF/ANSI 3723,000 gal each
Compare
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